JPWO2005082963A1 - Modified polyolefin resin - Google Patents

Abstract

Obtained by graft-modifying a propylene random copolymer having a melting point of 50 to 130 ° C. obtained by polymerization in the presence of a metallocene catalyst with an unsaturated carboxylic acid and / or a derivative thereof, and having a weight average molecular weight of 15,000 to The modified polyolefin resin having a graft weight of 200,000 and unsaturated carboxylic acid and / or derivative thereof is 0.2 to 50% by weight is a binder and primer for a substrate on which a paint or the like is difficult to adhere stably Suitable as an adhesive or the like. The polyolefin resin of the present invention is excellent in adhesion, gasohol resistance, blocking resistance and the like. Further, the polyolefin resin of the present invention is excellent in adhesion and the like even when subjected to low temperature baking.

Description

  The present invention relates to a modified polyolefin resin and a composition in which this is dissolved or dispersed in a solvent (hereinafter sometimes referred to as “modified polyolefin resin etc.”). More specifically, the present invention relates to a modified polyolefin resin suitable as an adhesive, a binder, a primer and the like.

  Polyolefin resins such as polypropylene and polyethylene are inexpensive and have many excellent properties such as moldability, chemical resistance, water resistance, and electrical properties, and thus have been widely used in recent years as sheets, films, molded articles, and the like. However, base materials made of these polyolefin resins (hereinafter referred to as polyolefin base materials) are nonpolar and crystalline, unlike polar base materials such as polyurethane resins, polyamide resins, acrylic resins, and polyester resins. It is difficult to paint and bond.

  Therefore, a pretreatment agent having adhesiveness to both the base material and the paint is applied in advance to the surface of the base material. Such a pretreatment agent has various names depending on applications, for example, a binder, a primer, or an adhesive. As the pretreatment agent, for example, a resin having a predetermined property is used, and a pretreatment agent such as a hot melt system that is melted by heating to form a binder or the like, or a solvent system that dissolves the resin in a solvent is provided.

  There is a method in which affinity with a polyolefin-based substrate is improved and adhesion is improved by using a chlorinated polyolefin resin as a coating composition. However, this method has problems such as the stability problem due to dehydrochlorination and the tendency to avoid the use of chlorine due to the recent increase in environmental awareness.

  Thus, acid-modified polyolefin resins such as unsaturated carboxylic acid modification have been proposed as compositions that do not use chlorine. However, among the conventional acid-modified polyolefin resins, those using a crystalline polyolefin resin as a raw material have high adhesive strength at high temperature adhesion and do not cause problems due to tack, but adhesion at low temperature adhesion Is not expressed and the solution property is generally not good.

  In order to solve these problems, amorphous polyolefin resin is used as a raw material. As such a resin, a propylene random copolymer is often used.

  The propylene-based random copolymer is obtained by breaking the crystallinity of polypropylene by adding another monomer during the production of polypropylene. However, the acid-modified product of the propylene-based random copolymer has low adhesion, has a tack on the dry coating film, and when applied to a film substrate, there is a problem of blocking during winding after coating. . In addition, there are problems such as poor solubility in non-aromatic solvents and solubility in aromatic solvents but poor solution stability.

  To solve such problems, for example, by reacting unsaturated carboxylic acid such as maleic anhydride graft-modified to polyolefin resin with polyester or alcohol, solvent solubility, long-term storage stability of the solution Etc. have been reported (for example, Patent Document 1). Moreover, it has been reported that the adhesive strength, solvent solubility, tackiness, and the like have been improved by modifying an amorphous polyolefin resin with an unsaturated carboxylic acid and an acrylic derivative (for example, Patent Document 2).

  However, in the production of propylene random copolymers, the production method using Ziegler-Natta catalyst, which has been widely used in the past, is generally difficult to precisely control the molecular weight and monomer composition. There are not a few structures in the random copolymer having a low molecular weight and a relatively large amount of ethylene component, or a structure having a high molecular weight and a relatively large amount of propylene component. The former is a cause of tackiness and adhesive strength reduction, and the latter is a cause of deterioration of solvent solubility and low-temperature adhesiveness. Therefore, the acid-modified products of conventional propylene random copolymers have limited physical properties.

  In recent years, organic solvent-based paints and adhesives have been avoided from the viewpoint of environmental problems, and pretreatment agents tend to move to aqueous systems. As an aqueous resin composition adhering to a polyolefin base material, it is disclosed by patent document 3, 4 etc., for example. However, since the conventional raw material resin used for the aqueous treatment is manufactured using a Ziegler-Natta catalyst, it is generally difficult to precisely control the molecular weight and monomer composition. Therefore, the obtained propylene-based random copolymer In addition to a broad molecular weight distribution (Mw / Mn), there are structures having a low molecular weight and a relatively large amount of ethylene components. For this reason, there existed a problem that the adhesiveness to a polyolefin base material, water resistance, gasohol resistance, and blocking resistance fell.

  For the purpose of improving these, there is a method of adding a crosslinking agent (for example, Patent Documents 5 and 6). However, since this method mixes other resins such as polyurethane-based or vinyl-based aqueous resins, there is a problem in adhesion to a polyolefin substrate.

  In addition, in recent years, in order to reduce energy and time during the drying / baking process after being applied to a base material, it has been emphasized that the aqueous resin composition is compatible with low-temperature baking and is highly solid. Low-temperature baking conditions are becoming more severe, and there are cases where the temperature is set to 60 ° C.

  A method for lowering the softening temperature of the raw material polypropylene random copolymer is effective as one of the means for low temperature baking. In recent years, it has become possible to produce a propylene random copolymer having a very narrow molecular weight distribution (Mw / Mn = about 2 or less) and a low melting point (Tm) using a metallocene catalyst. Development of an aqueous resin composition suitable for low-temperature baking (80 to 90 ° C.) by chlorinating and acid-modifying a polymer is underway (for example, Patent Document 7). Since the chlorinated resin described in Patent Document 6 has a lower melting point than non-chlorinated resins, the aqueous resin composition is suitable for low-temperature baking. However, with the recent increase in environmental awareness, a non-chlorine aqueous resin composition suitable for low temperature baking is desired.

  Further, an aqueous dispersion excellent in heat sealability by modifying an ethylene / α-olefin random copolymer generated from the metallocene catalyst is disclosed (for example, Patent Document 8). However, since the main component of this aqueous dispersion is ethylene, sufficient adhesion to other polyolefin substrates such as polypropylene is not obtained.

  In general, the acid-modified polyolefin aqueous resin composition is poorly compatible with other resins, and in the production of paints for painting and printing inks, other resins that can be mixed are limited. There was a problem that it was difficult to produce paints, inks or adhesives.

JP 11-217537 A JP 2002-173514 A Japanese Patent Laid-Open No. 6-256592 Special table 2001-504542 JP 2002-80686 JP-A-6-145286 JP 2003-327761 A Japanese Patent Laid-Open No. 2001-106838

This invention makes it a subject to provide the new resin excellent in the adhesiveness with respect to nonpolar base materials, such as polyolefin resin, especially a hard-to-adhere base material.
Furthermore, the present invention provides various properties required as a primer to be applied before coating of paints, etc .; for example, excellent water resistance, gasohol resistance, blocking resistance, storage stability; It is an object of the present invention to provide a resin having properties such as low; suitable for low-temperature baking; excellent compatibility with other resins; and a composition containing the same. Furthermore, this invention makes it a subject to provide resin excellent in the solubility with respect to a solvent, when using an organic solvent as a solvent. Furthermore, an object of the present invention is to provide an environmentally friendly resin composition suitable as a primer.

  In order to solve the above-mentioned problems, the present inventors have intensively studied. As a result, among the propylene random copolymers obtained using a metallocene catalyst as a polymerization catalyst, the melting point (Tm) by a differential scanning calorimeter (DSC). By using a resin obtained by graft-modifying an unsaturated carboxylic acid and / or derivative thereof alone or in combination with a (meth) acrylic acid compound, a resin having a temperature of 50 to 135 ° C. It has been found that such problems can be solved, and the present invention has been accomplished.

That is, the present invention provides the following modified polyolefin resin and its application.
(1) A propylene-based random copolymer having a melting point of 50 to 130 ° C. obtained by polymerization in the presence of a metallocene catalyst is graft-modified with an unsaturated carboxylic acid and / or a derivative thereof, and has a weight average molecular weight of 15 A modified polyolefin resin having an unsaturated carboxylic acid and / or its derivative graft weight of 0.2 to 50% by weight.
(2) A propylene-based random copolymer having a melting point of 50 to 130 ° C. obtained by polymerization in the presence of a metallocene catalyst is graft-modified with an unsaturated carboxylic acid and / or a derivative thereof and (meth) acrylic acid ester. The weight average molecular weight is 15,000 to 200,000, the graft weight of the unsaturated carboxylic acid and / or its derivative is 0.1 to 20% by weight, and the graft weight of the (meth) acrylic acid ester Is a modified polyolefin resin in which is 0.1 to 30% by weight.
(3) An adhesive comprising the modified polyolefin resin according to the above (1) or (2).
(4) A primer comprising the modified polyolefin resin according to (1) or (2) above.
(5) A coating binder containing the modified polyolefin resin according to (1) or (2) above.
(6) An ink binder comprising the modified polyolefin resin according to (1) or (2) above.
(7) A polyolefin substrate, an undercoat layer formed of the modified polyolefin resin described in (1) or (2), and a paint layer, wherein the undercoat layer is laminated on the polyolefin substrate, and the paint A polyolefin molded body in which the layer is laminated on the undercoat layer.
(8) A modified polyolefin resin composition comprising the modified polyolefin resin according to the above (1) or (2) and an organic solvent.
(9) A modified polyolefin resin composition comprising the modified polyolefin resin according to (1) or (2), water, and a surfactant, wherein the modified polyolefin resin dispersed in water has an average particle size of 300 nm or less. object.

  As a feature of the low melting point propylene random copolymer produced using a metallocene catalyst as a polymerization catalyst, the molecular weight distribution can be much narrower than that using a conventional Ziegler-Natta catalyst (Mw / Mn = about 2 or less). ). It was also found that a propylene random copolymer obtained by modifying it with an unsaturated carboxylic acid or a derivative thereof has a very narrow molecular weight distribution. Moreover, by using together with the unsaturated carboxylic acid and / or its derivative (A) and the (meth) acrylic acid compound (B) at the time of modification, the compatibility with other resins is improved and the low molecular weight due to the degradation of the polyolefin skeleton. Could be prevented.

  As described above, the modified polyolefin-based resin of the present invention is obtained by using a metallocene catalyst to narrow the molecular weight distribution, reduce low molecular weight substances, use regular crystallinity, and lower the melting point while maintaining crystallinity. Is excellent in adhesion, and is excellent in properties such as water resistance, gasohol resistance, and blocking resistance. The modified polyolefin resin of the present invention is also suitable for low temperature baking and high solidification. Furthermore, the modified polyolefin resin of the present invention has good compatibility with other resins.

The modified polyolefin resin of the present invention has good solubility in organic solvents.
In addition, the aqueous resin composition containing the modified polyolefin resin of the present invention has excellent performance in terms of adhesion to olefinic materials, blocking resistance, water resistance, gasohol resistance, etc. while being aqueous. Yes. Furthermore, there is no dispersion failure due to an increase in melt viscosity in the aqueous process, and the viscosity of the final product obtained does not increase, so that workability is good and suitable for high solidification, and low temperature of 60 to 90 ° C. Excellent adhesion to the substrate even under baking conditions.
Further, the modified polyolefin resin of the present invention is excellent in storage stability even after being dissolved in a solvent.

1. Modified polyolefin resin of the present invention The modified polyolefin resin of the present invention grafts a propylene random copolymer having a melting point of 50 to 130 ° C. obtained by polymerization in the presence of a metallocene catalyst with an unsaturated carboxylic acid and / or a derivative thereof. Obtained by denaturation.

  The propylene random copolymer used as a raw material in the present invention is a copolymer obtained by copolymerizing propylene as a main component and other α-olefin as a comonomer using a metallocene catalyst as a polymerization catalyst. is there. The content ratio (molar ratio) of propylene unit: other olefin unit as a constituent unit in the molecule is preferably 100: 0 to 90:10.

  As another α-olefin, at least one selected from the group consisting of ethylene or an olefin having 4 or more carbon atoms can be selected. Examples of the olefin having 4 or more carbon atoms include 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene and the like. When these are used, the melting point of the propylene random copolymer can be lowered.

  The melting point (Tm) of the propylene random copolymer used in the present invention is a relatively low value of 50 to 135 ° C., more preferably 70, as measured by a differential scanning calorimeter (DSC). ~ 90 ° C. When the melting point is higher than 135 ° C., the melt viscosity of the modified resin increases, and the workability in the aqueous process decreases. On the other hand, when the temperature is lower than 50 ° C., the crystallinity is lost, and adhesion to the material, blocking resistance, water resistance, and gasohol resistance are deteriorated.

  In particular, in applications such as a primer for an automobile bumper, solvent resistance (gasoline resistance, gasohol resistance, etc.) of the coating film is strongly required. When the melting point of the resin is too low, the solubility in a solvent increases and the solvent resistance of the coating film decreases. In addition, if the resin melting point is too high, the adhesion to the material during low-temperature baking is particularly poor, and the solvent resistance of the coating film also decreases. Therefore, it is important to use a raw material resin having an optimum melting point. In the propylene random copolymer which is the raw material of the present invention, those having a melting point of 70 to 90 ° C. exhibit very excellent solvent resistance as a primer for low temperature baking.

  Tm measurement by DSC in the present invention was performed by using a DSC measuring apparatus manufactured by Seiko Denshi Kogyo, and about 10 mg of sample was melted at 200 ° C. for 5 minutes and then cooled to −60 ° C. at a rate of 10 ° C./min for crystallization. Later, the temperature was further increased to 200 ° C. at 10 ° C./min, and evaluation was made based on the melting peak temperature when melting.

  The physical properties required for the resin of the present invention are high crystallinity and low melting point. In general, in the present invention, a copolymer using a metallocene catalyst is used in order to simultaneously realize the opposite physical properties of high crystallinity and low melting point, since the melting point is generally high when it is highly crystalline. Is preferred.

  When a copolymer is produced using a Ziegler-Natta catalyst that is generally used along with a metallocene catalyst, the following problems occur. Since the Ziegler-Natta catalyst is a multi-site catalyst and the catalytic active sites are not uniform, the present invention is intended to solve (i) crystallinity, (ii) composition distribution, and (iii) molecular weight distribution. Adversely affected. (I) means that it is difficult to control completely isotacticity, syndiotacticity, or arbitrarily control stereoregularity. As a result, the crystallinity is biased, and a low crystalline part and a high crystalline part exist in the polymer chain. The low crystalline part has a low cohesive force and causes a reduction in adhesion. In addition, since the highly crystalline portion remains, the melting point is high. In order to lower the melting point, it is necessary to break the crystallinity. However, when a Ziegler-Natta catalyst is used, precise control of tacticity is difficult, and it is difficult to effectively lower the melting point. Therefore, in order to lower the melting point, it is necessary to add other components such as ethylene. At that time, (ii) greatly affects the physical properties of the copolymer. When a Ziegler-Natta catalyst is used, other components such as ethylene are present unevenly in the copolymer. That is, there are a part (A) with a small amount of other components such as ethylene and a part (B) with a large amount. (A) inhibits the lowering of the melting point of the copolymer, and (B) causes tackiness and causes problems in adhesion and the like, and the object of the present invention cannot be achieved. (Iii) means that a polymer having a very wide molecular weight distribution from a low molecular weight to a high molecular weight is synthesized. As a result, the low molecular weight body causes a decrease in adhesion and the appearance of tack.

  On the other hand, the metallocene catalyst is a single-site catalyst, and since the catalytic active site is uniform, (i) crystallinity, (ii) composition distribution, and (iii) molecular weight distribution are problems to be solved by the present invention. It has a positive effect on it. (I) means that complete isotacticity and syndiotacticity can be arbitrarily controlled. Therefore, there is no bias in crystallinity, and a uniform polymer can be obtained with respect to the molecular structure: for example, the arrangement of propylene sites and other structural units; the content ratio of each structural unit, etc. Less likely to cause causative low crystalline sites. Furthermore, (i) also means that it is easy to arbitrarily control the stereoregularity, and when breaking the crystallinity to lower the melting point, other components are added because of the regularity of the crystallinity. Without breaking, the melting point can be lowered while maintaining crystallinity to some extent. Further, (ii) means that other components can be regularly introduced when other components are used in combination, and the melting point can be effectively lowered with a small addition amount. (Iii) means that a polymer having a very narrow molecular weight distribution is synthesized. As a result, a low molecular weight body is not produced, and adhesion strength is not lowered and tack is not exhibited. Therefore, a metallocene catalyst is preferable as the catalyst used for solving the problems of the present invention.

As one method for expressing the degree of molecular weight distribution, the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) of the polymer, Mw / Mn, can be used. In the case of monodispersion, this ratio is 1, and the larger the dispersion, the larger the value of this ratio.
In the present specification, the molecular weight distribution means a value obtained by dividing the weight average molecular weight (Mw) of the polymer by the number average molecular weight (Mn): Mw / Mn. The molecular weight distribution of the modified polyolefin resin of the present invention is preferably 3 or less as a guide. The weight average molecular weight can be determined by a known method such as GPC (gel permeation chromatography), light scattering method, etc., but the weight average molecular weight and number average molecular weight in this specification are It is the molecular weight measured by GPC method.

A well-known thing can be used for the metallocene catalyst used in this invention. Specifically, a catalyst obtained by combining components (a) and (b) described below and (c) as necessary is desirable.
Component (a): a metallocene complex which is a transition metal compound of Group 3 to 6 of the periodic table having at least one conjugated five-membered ring ligand.
Component (b): Cocatalyst capable of activating the metallocene complex (a) by reacting the compound (b) with the metallocene complex (a) Component (c): an organoaluminum compound.

  There is no restriction | limiting in particular in the molecular weight of the propylene type random copolymer used as a raw material by this invention. However, since the weight average molecular weight of the modified propylene random copolymer needs to be 15,000 to 200,000, when the weight average molecular weight of the propylene random copolymer is larger than 200,000, heat or radical It is necessary to adjust the molecular weight to an appropriate range by a known method such as degradation in the presence of. These can be used alone or in combination.

  Specific examples of the propylene random copolymer used in the present invention may include commercially available products such as Wintec (manufactured by Nippon Polypro Co., Ltd.).

  The unsaturated carboxylic acid used for graft modification in the present invention is an unsaturated hydrocarbon having a carboxyl group. The derivatives include anhydrides. As the unsaturated carboxylic acid and derivatives thereof used in the present invention, fumaric acid, maleic acid, itaconic acid, citraconic acid, aconitic acid and anhydrides thereof, methyl fumarate, ethyl fumarate, propyl fumarate, Butyl fumarate, dimethyl fumarate, diethyl fumarate, dipropyl fumarate, dibutyl fumarate, methyl maleate, ethyl maleate, propyl maleate, butyl maleate, dimethyl maleate, diethyl maleate, dipropyl maleate, maleic acid Dibutyl etc. are mentioned, More preferably, itaconic anhydride, maleic anhydride, etc. are illustrated.

  Good adhesion to olefinic substrates can be realized by modifying a propylene random copolymer using a metallocene catalyst as a production catalyst with an unsaturated carboxylic acid and / or derivative thereof, but in addition, (meth) acrylic compounds By modifying in combination, physical properties such as adhesion, solubility in non-toluene solvents, and compatibility with other resins are further improved. Actually, when used as a modified polyolefin resin as an adhesive, a primer or the like, it is often mixed with other resins, and compatibility is one of important properties.

  In this specification, the (meth) acrylic acid compound is a compound containing at least one (meth) acryloyl group in the molecule. Examples of the (meth) acrylic acid compound include (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, cyclohexyl (meth) acrylate, hydroxyethyl (meth) acrylate, Examples include isobornyl (meth) acrylate, glycidyl (meth) acrylate, octyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate, stearyl (meth) acrylate, and acrylamide. These can be used alone or in combination, and the mixing ratio can be freely set. In particular, those containing at least 20% by weight of at least one compound selected from (meth) acrylic acid esters represented by the following general formula (I) are preferable. By satisfying this condition, the molecular weight distribution can be made very narrow, and the solvent solubility of the modified polypropylene resin and the compatibility with other resins can be further improved. By modifying the above-mentioned propylene-based random copolymer having a melting point of 70 to 90 ° C. under the above conditions, a low-temperature baking-compatible primer having excellent solvent resistance can be obtained.

  In the modified polypropylene random copolymer of the present invention, the graft weight of the unsaturated carboxylic acid and / or derivative thereof is preferably 0.2 to 50% by weight, more preferably 0.5 to 15% by weight, Particularly preferably, it is 1 to 10% by weight. When the graft weight is less than this range, the adhesion of the coating composition to the adherend is lowered. On the other hand, when the amount is too large, many unreacted substances are generated, which is not preferable.

  When graft modification is performed using an unsaturated carboxylic acid and / or derivative thereof and a (meth) acrylic acid compound, the graft weight of the unsaturated carboxylic acid and / or derivative thereof is 0.1 to 20% by weight, More preferably, it is 0.5-15 weight%, Most preferably, it is 1-10 weight%, The graft weight of a (meth) acrylic acid compound is 0.1-30 weight%, More preferably, it is 0.5- 20% by weight. If the graft weight is less than this range, the compatibility and adhesion of the modified polypropylene random copolymer with other resins will be reduced. On the other hand, if the amount is too large, the reactivity is high, so an ultra high molecular weight body is formed, the melt viscosity increases, and the amount of homopolymer or copolymer that does not graft onto the polypropylene skeleton increases. In addition, the grafted weight% of the unsaturated carboxylic acid derivative and / or its acid anhydride (A) is determined by an alkali titration method. When the derivative is an ester having no acid group, it is determined by FT-IR or NMR. It is done. In the present invention, the graft weight% is determined by the alkali titration method when the alkali titration method is applicable, and is determined by FT-IR or NMR otherwise. The graft weight of the (meth) acrylic acid compound can be determined by NMR.

  The method for obtaining the modified propylene random copolymer can be carried out by a known method. For example, a solution method in which a propylene random copolymer is dissolved by heating in a solvent such as toluene and the above compound is added, or the above compound is added to a propylene random copolymer melted using a Banbury mixer, a kneader, an extruder, or the like. And a melting method in which is added. When adding, it may be added sequentially or all at once. Depending on the purpose of use, in order to improve the grafting efficiency of unsaturated carboxylic acid derivatives and / or anhydrides thereof, styrene, o-, p-, α-methylstyrene, divinylbenzene, hexadiene, Dicyclopentadiene or the like can also be added.

  The weight average molecular weight of the modified propylene random copolymer is 15,000 to 200,000. If it is less than 15,000, the adhesion and cohesive force to the nonpolar substrate are poor, and if it is more than 200,000, workability decreases due to an increase in melt viscosity during the production of the aqueous resin composition. In addition, the measuring method of a weight average molecular weight is as above-mentioned.

  The modified polyolefin resin of the present invention has low adhesion and adhesiveness, and can function as an intermediate medium for substrates that are difficult to apply and adhere to, such as paints. For example, the adhesion stability of the paint can be improved by laminating the modified polyolefin resin of the present invention on the surface of a base material made of polyolefin resin by a hot melt method, and further applying a paint or the like thereon. it can. Moreover, it is useful also as adhesion | attachment of polyolefin resin with poor adhesiveness. That is, the modified polyolefin resin of the present invention can be suitably used as an adhesive, primer, paint binder, ink binder, and the like.

  As an adherend (base material) that can suitably use the modified polyolefin resin of the present invention, sheets of nonpolar base materials such as polypropylene, polyethylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, and film formation Examples are things. The water-based resin of the present invention is characterized in that it can be used even if these substrates are difficult-to-adhere those that have not been surface-treated with plasma, corona, etc. Can be used as well.

2. Organic Solvent Resin Composition of the Present Invention As another aspect of the present invention, a modified polyolefin resin composition in which a modified polyolefin resin is dissolved or dispersed in a solvent is provided. First, the form which uses an organic solvent as a solvent is demonstrated.
Examples of the organic solvent include aromatic solvents such as toluene and xylene, aliphatic solvents such as cyclohexane, methylcyclohexane, ethylcyclohexane, nonane, and decane, ester solvents such as ethyl acetate and butyl acetate, acetone, methyl ethyl ketone, and methylbutyl. Examples thereof include ketone solvents such as ketones, alcohol solvents such as methanol, ethanol, propanol, and butanol, or mixtures of the above solvents. From the viewpoint of environmental problems, it is preferable to use a mixture of a cyclohexane aliphatic solvent and an ester or ketone solvent.

  The organic solvent-based modified polyolefin resin composition is particularly excellent in adhesion and the like, and can be used as an adhesive for non-polar substrates, a primer, a binder resin for paints, and a binder resin for inks. Moreover, you may change and use into forms, such as a solution, a powder, a sheet | seat, according to the necessity, such as a use. At that time, additives such as antioxidants, light stabilizers, ultraviolet absorbers, pigments, dyes, inorganic fillers and the like can be blended as necessary.

  In adhesives and ink binder resins, not only nonpolar substrates such as polyethylene and polypropylene but also polar substrates such as polyester, polyurethane and polyamide are often used together. Since it has adhesion to a substrate, it is suitable for the same application.

  Similarly, when used as a primer or a binder resin for paints, it is also suitable for the same application because of its excellent adhesion to top coats and clears. The modified polyolefin resin of the present invention is excellent in compatibility with other resins. When used as a binder for paints and inks, other resins such as urethane resin, epoxy resin, acrylic resin, phenol resin, alkyd resin, polyamide resin, polyimide resin, silicone resin, and nitrified cotton can be blended as necessary.

3. Aqueous resin composition of the present invention As another aspect of the present invention, there is provided a modified polyolefin resin composition comprising the modified polyolefin resin of the present invention, water, and a surfactant.

In the present invention, a surfactant is used to disperse and emulsify the resin of the present invention in water.
As the surfactant in the present invention, either a nonionic surfactant or an anionic surfactant can be used. Nonionic surfactants are preferred because they have a better influence on the water resistance of the emulsified aqueous resin composition.

  Nonionic surfactants include polyoxyethylene alkyl ether, polyoxyethylene alkylene alkyl ether, polyoxyethylene derivatives, polyoxyethylene fatty acid ester, polyoxyethylene polyhydric alcohol fatty acid ester, polyoxyethylene propylene polyol, sorbitan fatty acid ester, Examples include polyoxyethylene hydrogenated castor oil, polyoxyalkylalkylene polycyclic phenyl ether, polyoxyethylene alkylamine, alkylalkanolamide, polyalkylene glycol (meth) acrylate, and the like. Preferably, polyoxyethylene alkyl ether, polyoxyethylene fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene alkylamine and the like can be mentioned.

  Anionic surfactants include alkyl sulfates, polyoxyethylene alkyl ether sulfates, alkylbenzene sulfonates, alpha olefin sulfonates, methyl taurates, sulfosuccinates, ether sulfonates, ether carboxylates, fatty acids Examples include salts, naphthalenesulfonic acid formalin condensates, alkylamine salts, quaternary ammonium salts, alkylbetaines, alkylamine oxides, and the like, and preferably polyoxyethylene alkyl ether sulfates, sulfosuccinates and the like.

  The addition amount of the surfactant is 0.1 to 30% by weight, more preferably 5 to 20% by weight, based on the modified polyolefin resin composition. If the amount is more than 30% by weight, an amount of emulsifier sufficient to form an aqueous resin composition will be present in the system, resulting in a markedly reduced adhesion and a plastic effect when formed into a dry film. , Causing a bleed phenomenon, and blocking is likely to occur.

  The aqueous resin composition in the present invention preferably has a pH of 5 or more, and particularly preferably pH = 6-10. If the pH is less than 5, neutralization is insufficient, so that the modified polyolefin resin does not disperse in water, or even if dispersed, precipitation / separation tends to occur with time, and storage stability deteriorates. In addition, at pH = 10 or more, there is a problem in compatibility with other components and work safety. A basic substance may be added for the purpose of neutralizing the acid component in the modified polyolefin resin composition and dispersing it in water. The basic substance is preferably sodium hydroxide, potassium hydroxide, ammonia, methylamine, propylamine, hexylamine, octylamine, ethanolamine, propanolamine, diethanolamine, N-methyldiethanolamine, dimethylamine, diethylamine, triethylamine, N , N-dimethylethanolamine, 2-dimethylamino-2-methyl-1-propanol, 2-amino-2-methyl-1-propanol, morpholine, etc., more preferably ammonia, triethylamine, 2-amino-2. -Methyl-1-propanol, morpholine and the like. The amount used can be arbitrarily added from the amount of the acid component of the modified polyolefin resin composition, but it must be added so that the pH of the aqueous resin composition is 5 or more, preferably 6 to 10.

  In the aqueous resin composition of the present invention, the average particle size of the resin emulsified and dispersed in water is preferably 300 nm or less, more preferably 200 nm or less. When it is 300 nm or more, the storage stability of the aqueous resin composition and the compatibility with other resins deteriorate, and further, the physical properties of the film such as adhesion to a substrate, gasohol resistance, water resistance, and blocking resistance decrease. To do. The average particle diameter is preferably adjusted to 50 nm or more. The particle size can be made as small as possible, but in this case, generally, the amount of emulsifier added increases, and the physical properties of the film such as adhesion to the substrate, water resistance, gasohol resistance, etc. tend to decrease. Becomes easier to appear. In addition, the value of the average particle diameter in this specification is obtained by the particle size distribution measurement using the light scattering method. The particle diameter can be adjusted by the amount and type of emulsifier added, the stirring force when emulsifying the resin in water, and the like.

  The emulsification method of the aqueous resin composition may be any of the known forced emulsification method, phase inversion emulsification method, D phase emulsification method, gel emulsification method, etc., and the equipment used is independent stirring with a stirring blade, a disper, a homogenizer, etc. It is possible to use a composite stirring, sand mill, or multi-screw extruder that combines these. However, in order to reduce the average particle size of the aqueous resin composition to 300 nm or less, a phase inversion emulsification method or a method using a composite stirring, a sand mill, a multi-screw extruder or the like having a high shear force is preferable.

  In this invention, you may use a crosslinking agent for the said aqueous resin composition according to a use and the objective. The crosslinking agent means a compound that reacts with active hydrogen such as hydroxyl group, carboxyl group, amino group, etc. present in a modified polyolefin resin, surfactant, basic substance, etc. to form a crosslinked structure, and may itself be water-soluble. It may be dispersed in water by some method. Specific examples include blocked isocyanate compounds, aliphatic or aromatic epoxy compounds, amine compounds, amino resins, and the like.

  The method for adding the crosslinking agent is not particularly limited. For example, you may mix | blend in the middle of an aqueous-ized process, and may add after aqueous-ized.

  In addition, the aqueous resin composition of the present invention includes an aqueous acrylic resin, an aqueous urethane resin, a lower alcohol, a lower ketone, a lower ester, an antiseptic, a leveling agent, an antioxidant, a light stabilizer, and an ultraviolet absorber depending on applications. Agents, dyes, pigments, metal salts, acids and the like can be blended.

4). Molded Article Laminated with Modified Polyolefin Resin The modified polyolefin resin of the present invention having the characteristics as described above is extremely useful as a primer or the like for a polyolefin substrate that is difficult to adhere to, such as paint. For example, the modified polyolefin resin or resin composition of the present invention is applied to the surface of a polyolefin substrate to form an undercoat layer, and a paint or the like is applied thereon. The obtained molded article is excellent in adhesion stability of paints and the like.

  An example of a molded article made of a polyolefin resin and a base material is a bumper for automobiles. In automobile bumpers and the like, there are particularly strict requirements for performance such as gasohol resistance and gasoline resistance. As described above, the modified polyolefin resin of the present invention is excellent in performances such as gasohol resistance and gasoline resistance in addition to adhesion, and thus can be an automobile bumper excellent in these performances. In bumper manufacturing, there is a strong demand for low temperature baking in order to reduce costs. Since the molded product of the present invention exhibits excellent performance such as adhesion at low temperatures and baking, it can be manufactured at low cost. In recent years, environmental considerations are particularly required. Since the modified polyolefin resin of the present invention is excellent in adhesiveness as an aqueous resin composition, it can be produced in consideration of the environment.

  EXAMPLES Next, although an Example demonstrates this invention still in detail, this invention is not limited to this. In addition, the weight average molecular weight and graft weight shown in the prototype were measured after washing the modified polyolefin resin composition with a large amount of methanol.

The weight average molecular weight and the number average molecular weight are measured by GPC method, and the graft weight is an alkali titration method for unsaturated carboxylic acid derivatives having an acid group, and in the case of an ester having no acid group, In the case of a (meth) acrylic acid compound by FT-IR, it was measured by NMR.
The average particle size of the aqueous resin composition was measured by a light scattering method.

Each measurement condition is shown below.
[GPC]
Measurement was performed using a high-speed GPC apparatus (HLC-8120GPC manufactured by Tosoh Corporation).
Measurement condition:
Column: TSKgel (G6000HXL, G5000HXL, G4000HXL, G3000HXL, G2000HXL)
Column temperature: 40 ° C
Detector: RI
Developing solvent: THF

[Alkali titration method]
Neutralization titration with a 1 mol / l methanol solution of KOH was performed.

[FT-IR]
Measurement was performed using an FT-IR measuring instrument (FT-IR-350 manufactured by JASCO Corporation).
Resolution: 4cm-1

[NMR]
The measurement was performed using an NMR measurement instrument (Varian Mercury 400 type nuclear magnetic resonance apparatus).
Measurement condition:
Observation nucleus: 1H, 13C
Measuring solvent: Mixed solution of o-dichlorobenzene and benzene-d6 Measuring temperature: 135 ° C

[Light scattering method]
PCS (Photon Correlation) using a particle size measurement device (ZETASIZER 3000HAS manufactured by MALVERN Instruments)
Spectroscopy) method.

MFR in the examples is an abbreviation for Melt Flow Rate. MFR is an index indicating the melt flowability of the resin, and is a value measured by a test method defined in JIS K7210.
[Example 1]
A biaxial propylene-based random copolymer (97 mol% propylene component, 3 mol% ethylene component, MFR = 2.0 g / 10 min, Tm = 125 ° C.) produced using a metallocene catalyst as a polymerization catalyst was set at a barrel temperature of 350 ° C. The resultant was supplied to an extruder and subjected to thermal degradation to obtain a propylene random copolymer having a melt viscosity at 190 ° C. of about 2000 mPa · s. In a four-necked flask equipped with a stirrer, a condenser tube, and a dropping funnel, 100 g of this resin was dissolved in 400 g of toluene by heating, and the system temperature was maintained at 110 ° C while stirring. 1 g of oxide was added dropwise, followed by degradation for 1 hour. Next, 5 g of itaconic anhydride and 2.0 g of benzoyl peroxide were added dropwise over 3 hours, followed by further reaction for 1 hour. After the reaction, after cooling to room temperature, the reaction product is put into a large amount of acetone and purified to obtain a modified propylene resin having a weight average molecular weight of 75,000 and an itaconic anhydride graft weight of 4.1% by weight. It was.

[Example 2]
100 parts by weight of a propylene random copolymer produced using a metallocene catalyst as a polymerization catalyst (97 mol% of propylene component, 3 mol% of ethylene component, MFR = 7.0 g / 10 min, Tm = 125 ° C.), 8 parts by weight of maleic anhydride Then, 10 parts by weight of methyl methacrylate and 3 parts by weight of dicumyl peroxide were reacted using a twin screw extruder set at 180 ° C. Deaeration was also performed in the extruder to remove residual unreacted substances. The resulting modified polypropylene resin had a weight average molecular weight of 95,000, a maleic anhydride graft weight of 5.7 wt%, and a methyl methacrylate graft weight of 6.4 wt%.

[Example 3]
Propylene random copolymer produced using a metallocene catalyst as a polymerization catalyst (propylene component 96%, ethylene component 4 mol%, weight average molecular weight 65,000, Tm = 80 ° C.) 100 parts by weight, maleic anhydride 8 parts by weight, methacryl The reaction was carried out using a twin screw extruder in which 4 parts by weight of lauryl acid, 4 parts by weight of stearyl methacrylate, and 3 parts by weight of di-t-butyl peroxide were set at 180 ° C. Deaeration was also performed in the extruder to remove residual unreacted substances. The resulting modified polypropylene resin had a weight average molecular weight of 66,000, a maleic anhydride graft weight of 6.0% by weight, a lauryl methacrylate graft weight of 3.2% by weight, and a stearyl methacrylate graft weight of 3. It was 1% by weight.

[Example 4]
Propylene random copolymer produced using a metallocene catalyst as a polymerization catalyst (propylene component 96%, ethylene component 4 mol%, weight average molecular weight 55,000, Tm = 67 ° C.) 100 parts by weight, maleic anhydride 8 parts by weight, methacryl The reaction was carried out using a twin screw extruder in which 4 parts by weight of lauryl acid, 4 parts by weight of stearyl methacrylate, and 3 parts by weight of di-t-butyl peroxide were set at 180 ° C. Deaeration was also performed in the extruder to remove residual unreacted substances. The resulting modified polypropylene resin had a weight average molecular weight of 58,000, a maleic anhydride graft weight of 6.1 wt%, a lauryl methacrylate graft weight of 3.1 wt%, and a stearyl methacrylate graft weight of 3. It was 1% by weight.

[Example 5]
Propylene random copolymer produced using a metallocene catalyst as a polymerization catalyst (propylene component 96 mol%, ethylene component 4 mol%, weight average molecular weight 55,000, Tm = 67 ° C.) 100 g, toluene 400 g were stirred, cooling tube, In a four-necked flask equipped with a dropping funnel, the temperature of the system is maintained at 110 ° C. and dissolved by heating, then 14 g of maleic anhydride, 8 g of acrylic acid, 8 g of cyclohexyl methacrylate, 9 g of tridecyl methacrylate, peroxide 3.5 g of benzoyl was added dropwise over 3 hours, and the reaction was further continued for 1 hour. After the reaction, after cooling to room temperature, the reaction product was put into a large amount of acetone for purification, and the weight average molecular weight was 62,000, the grafting weight of maleic anhydride was 7.2% by weight, and the grafting weight of acrylic acid. A modified propylene resin having a 4.9 wt% cyclohexyl methacrylate graft weight and a 5.2 wt% tridecyl methacrylate graft weight was obtained.

[Comparative Examples 1 and 2]
For each of Examples 1 and 2, a propylene random copolymer produced using a Ziegler-Natta catalyst instead of the propylene random copolymer produced using a metallocene catalyst as a polymerization catalyst (72 mol% propylene component, ethylene component) The same modification reaction was carried out using 7 mol%, butene component 21 mol%, weight average molecular weight 120,000, Tm = 100 ° C.) as a raw material resin, and the resins of Comparative Examples 1 and 2 were obtained.
[Comparative Example 3]
In Example 3, a propylene random copolymer produced using a Ziegler-Natta catalyst instead of the propylene random copolymer produced using a metallocene catalyst as a polymerization catalyst (propylene component 68 mol%, ethylene component 8 mol%, A similar modification reaction was performed using a butene component of 24 mol%, a weight average molecular weight of 50,000, and Tm = 70 ° C. as a raw material resin.

[Comparative Example 4]
In Example 5, a propylene random copolymer produced using a Ziegler-Natta catalyst instead of the propylene random copolymer produced using a metallocene catalyst as a polymerization catalyst (68 mol% propylene component, 8 mol% ethylene component, A similar modification reaction was performed using a butene component of 24 mol%, a weight average molecular weight of 50,000, and Tm = 70 ° C. as a raw material resin.

〔Test method〕
A 15% by weight toluene solution was prepared for each of the modified polypropylene resins obtained in Examples 1 to 5 and Comparative Examples 1 to 4, and the following tests were performed.

Test 1: Solvent solubility test The solution properties of the toluene solution after one week were observed. The results are shown in Table 1.
Evaluation criteria:
○: Precipitation did not occur and no buds were observed. Δ: Slight precipitation and / or tub formation was observed. X: Generation of tubs was remarkable, insoluble, or two-layer separation.

Test 2: Adhesive strength test Adhesiveness to polypropylene and PET:
The toluene solution was applied to a biaxially stretched polypropylene film or PET film that had not been surface-treated using a # 16 Meyer bar and dried at room temperature for 24 hours. After drying, it is superimposed on a biaxially stretched polypropylene film or PET film that has not been applied. Heat sealing was performed using a 276 heat seal tester (Yasuda Seiki Seisakusho) under the conditions of 1.5 kgf / cm 2, 110 ° C. and 3 seconds. Each test piece was cut to a width of 15 mm, peeled off at 100 mm / min using a tensile tester, and the peel strength was measured. The test was performed three times, and the average value was taken as the result. The results are shown in Table 1.

Adhesion to aluminum foil:
The toluene solution was applied to an aluminum foil not subjected to rolling oil treatment using a # 16 Meyer bar and dried at room temperature for 24 hours. After drying, it is superposed with an unstretched polypropylene film. Heat sealing was performed using a 276 heat seal tester (Yasuda Seiki Seisakusho) under the conditions of 1.5 kg / cm 2, 200 ° C. and 1 second. Each test piece was cut to a width of 15 mm, peeled off at 100 mm / min using a tensile tester, and the peel strength was measured. The test was performed three times, and the average value was taken as the result. The results are shown in Table 1.

Test 3: Tackiness test [Finger tack test]
The toluene solution was applied to a biaxially stretched polypropylene film that had not been surface-treated using a # 16 Meyer bar and dried at room temperature for 24 hours. After drying, the film was bent so that the coated surfaces overlapped, and after lightly pressing with a finger, the film was peeled off, and the tack was evaluated from the ease of peeling. The results are shown in Table 1.

Evaluation criteria:
None: Immediately after releasing the finger, the film separates and no tack is recognized.
Weak: After releasing the finger, put a breath and the film will detach.
Middle: The film separates after a few seconds after releasing the finger.
Strong: After releasing the finger, the film does not detach even after 10 seconds.

[Heating and heating tack test]
The toluene solution was applied to a biaxially stretched polypropylene film that had not been surface-treated using a # 16 Meyer bar and dried at room temperature for 24 hours. After drying, the film was superposed on an uncoated biaxially stretched polypropylene film, applied with a load of 30 gf / cm ² , and stored in an atmosphere of 10% RH or less and 50 ° C. After 24 hours, the laminated film was peeled off, and tack was evaluated from the ease of peeling.

Evaluation criteria:
No: There is no catch when peeling.
Weak: Some catching occurs when peeling.
Middle: A catch occurs when peeling, and when the test piece is chopped and pulled with a tensile tester in the same manner as the heat seal strength test described above, a peel strength of 100 gf or more is exhibited.
Strong: A strong catch occurs when peeling, and when the test piece is chopped and pulled with a tensile tester in the same manner as the heat seal strength test described above, a peel strength of 200 gf or more is exhibited.

Test 4: Primer test The above toluene solution was spray-coated on an ultra-high rigidity polypropylene plate so that the dry film thickness was 10 to 15 μm and dried at 80 ° C. for 30 minutes. Next, the two-component top coat white paint was applied by spraying so that the dry film thickness was 45 to 50 μm, and allowed to stand at room temperature for 15 minutes, followed by baking at 90 ° C. for 30 minutes. The test piece was allowed to stand at room temperature for 3 days, and then the same test as the paint test was performed. The results are shown in Table 2.

[Adhesiveness]
100 grids reaching the substrate at intervals of 2 mm were formed on the coated surface, and a cellophane adhesive tape was adhered to the coated surface and peeled in the direction of 180 degrees, and the degree of remaining coating was determined.

[Moisture resistance]
After immersing the coated plate in warm water of 40 ° C for 240 hours, make 100 grids that reach the substrate at 2mm intervals on the coated surface, adhere cellophane adhesive tape on it and pull it off in 180 ° direction, and paint Judgment was made based on the degree of remaining film.

[Peel strength]
An exposed cloth is attached to the surface of each coating film using a water-based adhesive, and the backing is lined. A 1 mm wide cut is made with a cutter knife from above the cloth, and carefully peeled off from the edge to the middle so as to be peeled off between the substrate and the coating film of the present invention. The specimen prepared in this manner was peeled off at 100 mm / min using a tensile tester, and the peel strength was measured.

[Gasoline resistance]
Scratches (x marks) reaching the substrate were put on the surface of each coating film with a cutter knife, immersed in gasoline, and the state of the coating film was visually observed.

Evaluation criteria:
◎: No change after 12 hours ○: Film peeling occurred after 2-12 hours Δ: Film peeling occurred after 30 minutes to 2 hours x: Paint peeling occurred within 30 minutes

[Gaso-hole resistance]
Scratches (x marks) reaching the substrate were put on the surface of each coating film with a cutter knife, immersed in a solution in which gasoline and ethanol were mixed in 9/1 (vol / vol), and the state of the coating film was visually observed.

Evaluation criteria:
◎: No change after 12 hours ○: Film peeling occurred after 2-12 hours Δ: Film peeling occurred after 30 minutes to 2 hours x: Paint peeling occurred within 30 minutes

Test 5: Ink test 130 g of the above toluene solution and 20 g of titanium dioxide were kneaded for 3 hours with a sand mill, and then diluted with toluene so as to obtain a viscosity of 25 to 30 seconds / 20 ° C. in a # 3 Zahn cup to prepare an ink. About the obtained ink, the adhesive tape peeling test and the heat seal test were done as follows. The results are shown in Table 2.

[Adhesive tape peel test]
The prepared ink was applied to an untreated polypropylene film (hereinafter referred to as untreated PP) using a # 14 Meyer bar, dried at room temperature for 24 hours, and then a cellophane adhesive tape was applied to the ink-coated surface and weakly peeled off. And the state of the coated surface when it peeled strongly was investigated.

Evaluation criteria:
Good: No peeling at all Poor: There is peeling

[Heat seal test]
Ink was applied to untreated PP in the same manner as in the adhesive tape peel test, and dried at room temperature for 24 hours. Heat sealing was performed using a 276 heat seal tester (Yasuda Seiki Seisakusho) under the conditions of 1.5 kg / cm ² , 110 ° C. and 3 seconds. Each test piece was cut to a width of 15 mm, peeled off at 100 mm / min using a tensile tester, and the peel strength was measured. The test was performed three times, and the average value was taken as the result.

[Example 6] (Prototype Example 1)
Propylene-based random copolymer produced using a metallocene catalyst as a polymerization catalyst (propylene component 97%, ethylene component 3 mol%, MFR = 7.0 g / 10 min, Tm = 125 ° C.) 100 parts by weight, itaconic anhydride 8 parts by weight, The reaction was carried out using a twin screw extruder in which 3 parts by weight of di-t-butyl peroxide was set at 160 ° C. Deaeration was also performed in the extruder to remove residual unreacted substances. The resulting modified polypropylene resin had a weight average molecular weight of 98,000, a molecular weight distribution (Mw / Mn) of 2.7, and a graft weight of itaconic anhydride of 5.8% by weight.

[Example 7] (Prototype Example 2)
Propylene random copolymer produced using a metallocene catalyst as a polymerization catalyst (propylene component 96%, ethylene component 4 mol%, weight average molecular weight 55,000, Tm = 67 ° C.) 100 parts by weight, maleic anhydride 8 parts by weight, methacryl 8 parts by weight of methyl acid and 3 parts by weight of dicumyl peroxide were reacted using a twin screw extruder set at 180 ° C. Deaeration was also performed in the extruder to remove residual unreacted substances. The resulting modified polypropylene resin has a weight average molecular weight of 58,000, a molecular weight distribution (Mw / Mn) of 2.6, a maleic anhydride graft weight of 5.7% by weight, and a methyl methacrylate graft weight of 6. It was 4% by weight.

[Example 8] (Prototype example 3)
100 parts by weight of a propylene random copolymer (97% by mole of propylene component, 3% by mole of ethylene component, MFR = 7.0 g / 10min, Tm = 125 ° C.) produced using a metallocene catalyst as a polymerization catalyst, 8 parts by weight of itaconic anhydride The reaction was performed using a twin screw extruder in which 8 parts by weight of stearyl methacrylate and 3 parts by weight of di-t-butyl peroxide were set at 180 ° C. Deaeration was also performed in the extruder to remove residual unreacted substances. The resulting modified polypropylene resin has a weight average molecular weight of 75,000, a molecular weight distribution (Mw / Mn) of 3.0, an itaconic anhydride graft weight of 6.1% by weight, and a stearyl methacrylate graft weight of 6.2. % By weight.

[Example 9] (Prototype example 4)
100 parts by weight of a propylene random copolymer produced using a metallocene catalyst as a polymerization catalyst (97 mol% of propylene component, 3 mol% of ethylene component, MFR = 7.0 g / 10 min, Tm = 125 ° C.), 8 parts by weight of maleic anhydride , 2 parts by weight of acrylic acid, 2 parts by weight of cyclohexyl methacrylate, 2 parts by weight of tridecyl methacrylate and 3 parts by weight of di-t-butyl peroxide were reacted using a twin screw extruder set at 160 ° C. Deaeration was also performed in the extruder to remove residual unreacted substances. The resulting modified polypropylene resin had a weight average molecular weight of 133,000, a molecular weight distribution (Mw / Mn) of 3.2, a maleic anhydride graft weight of 5.8 wt%, and an acrylic acid graft weight of 1.2 weight. %, The graft weight of cyclohexyl methacrylate was 1.3% by weight, and the graft weight of tridecyl methacrylate was 1.0% by weight.

[Example 10] (Prototype example 10)
Propylene-based random copolymer produced using a metallocene catalyst as a polymerization catalyst (propylene component 96 mol%, ethylene component 4 mol%, weight average molecular weight 65,000, Tm = 80 ° C.) 100 parts by weight, maleic anhydride 8 parts by weight, 8 parts by weight of methyl methacrylate and 3 parts by weight of dicumyl peroxide were reacted using a twin screw extruder set at 180 ° C. Deaeration was also performed in the extruder to remove residual unreacted substances. The resulting modified polypropylene resin has a weight average molecular weight of 66,000, a molecular weight distribution (Mw / Mn) of 2.5, a maleic anhydride graft weight of 5.6% by weight, and a methyl methacrylate graft weight of 6. It was 5% by weight.

[Comparative Example 5] (Prototype Example 5)
Instead of a propylene random copolymer produced using a metallocene catalyst as a polymerization catalyst, a propylene random copolymer produced using a Ziegler-Natta catalyst (propylene component 72 mol%, ethylene component 7 mol%, butene component 21 mol) %, Weight average molecular weight 120,000, Tm = 100 ° C.) as a raw material resin, otherwise the same modification reaction as in Example 6 (Prototype Example 1) was performed, and the weight average molecular weight was 82,000, A modified propylene resin having a Mw / Mn) of 5.5 and a maleic anhydride graft weight of 5.2% by weight was obtained.

[Comparative Example 6] (Prototype Example 6)
Instead of the propylene random copolymer produced using a metallocene catalyst as a polymerization catalyst, a propylene random copolymer produced using a Ziegler-Natta catalyst (propylene component 68 mol%, ethylene component 8 mol%, butene component 24 mol) %, Weight average molecular weight 50,000, Tm = 70 ° C.) was used as a raw material resin, and the same modification reaction as in Example 7 (Prototype Example 2) was performed. The weight average molecular weight was 55,000, the molecular weight distribution (Mw / Mn) was obtained, and a modified propylene resin having a graft weight of maleic anhydride of 5.9% by weight and a methyl methacrylate graft weight of 6.3% by weight was obtained.

[Comparative Example 7] (Prototype Example 7)
Instead of the propylene random copolymer produced using a metallocene catalyst as a polymerization catalyst, a propylene random copolymer produced using a Ziegler-Natta catalyst (propylene component 68 mol%, ethylene component 8 mol%, butene component 24 mol) %, Weight average molecular weight 50,000, Tm = 70 ° C.) was used as a raw material resin, the same modification reaction as in Example 8 (Prototype Example 3) was carried out, the weight average molecular weight was 57,000, the molecular weight distribution (Mw / Mn) was 7.2, a modified propylene resin having an itaconic anhydride graft weight of 6.0% by weight and a stearyl methacrylate graft weight of 5.9% by weight was obtained.

[Comparative Example 8] (Prototype Example 8)
Instead of a propylene random copolymer produced using a metallocene catalyst as a polymerization catalyst, a propylene random copolymer produced using a Ziegler-Natta catalyst (propylene component 72 mol%, ethylene component 7 mol%, butene component 21 mol) %, Weight average molecular weight 120,000, Tm = 100 ° C.), using a twin screw extruder set at 190 ° C., and otherwise performing the same modification reaction as in Example 9 (Prototype Example 4). The average molecular weight is 140,000, the molecular weight distribution (Mw / Mn) is 6.2, the grafting weight of maleic anhydride is 6.6% by weight, the grafting weight of acrylic acid is 1.4% by weight, the grafting weight of cyclohexyl methacrylate A modified propylene resin having 1.6% by weight and 1.2% by weight of the graft weight of tridecyl methacrylate was obtained.

[Comparative Example 9] (Prototype Example 9)
The type of propylene random copolymer produced using a metallocene catalyst as a polymerization catalyst was changed to a propylene random copolymer having different specifications (manufactured by Sun Allomer Co., Ltd., MFR = 45.0 g / 10 min, Tm = 148 ° C.), Otherwise, the same modification reaction as in Example 8 (Prototype Example 3) was performed, the weight average molecular weight was 220,000, the molecular weight distribution (Mw / Mn) was 2.8, and the graft weight of itaconic anhydride was 5.8% by weight. A modified propylene resin having a graft weight of stearyl methacrylate of 6.2% by weight was obtained.

[Example 11]
In a four-necked flask equipped with a stirrer, a condenser, a thermometer and a dropping funnel, 100 parts by weight of the modified polyolefin resin obtained in Example 6 (Prototype Example 1), polyoxyethylene alkyl ether sulfate as a surfactant 10 parts by weight was added and kneaded at 120 ° C. for 30 minutes. Next, 10 parts by weight of dimethylethanolamine was added over 5 minutes, held for 5 minutes, and then 300 parts by weight of 90 ° C. ion exchange water was added over 40 minutes. Subsequently, the mixture was cooled to room temperature with stirring to obtain an aqueous resin composition. The solid content of the aqueous resin composition was 30% by weight, pH = 7.5, the viscosity was 47 mPa · s / 25 ° C., and the average particle size was 122 nm.

[Example 12]
100 parts by weight of the modified polyolefin resin obtained in Example 7 (Prototype Example 2) was used, and the surfactant was changed to 10 parts by weight of polyoxyethylene alkylamine. A resin composition was obtained. The solid content of the aqueous resin composition was 30% by weight, pH = 7.9, the viscosity was 76 mPa · s / 25 ° C., and the average particle size was 86 nm.

[Example 13]
The modified polyolefin resin obtained in Example 8 (Prototype Example 3) was used in an amount of 300 parts by weight, and the surfactant was changed to 10 parts by weight of polyoxyethylene alkyl ether sulfate. An aqueous resin composition was obtained. The solid content of the aqueous resin composition was 50% by weight, pH = 6.8, the viscosity was 136 mPa · s / 25 ° C., and the average particle size was 75 nm.

[Example 14]
In a four-necked flask equipped with a stirrer, a condenser, a thermometer and a dropping funnel, 100 parts by weight of the modified polyolefin resin obtained in Prototype Example 4, 10 parts by weight of polyoxyethylene alkylamine as a surfactant, methylcyclohexane 18 A part by weight was added and kneaded at 120 ° C. for 30 minutes. Next, 10 parts by weight of morpholine was added over 5 minutes, held for 5 minutes, and then 300 parts by weight of 90 ° C. ion exchange water was added over 40 minutes. A vacuum treatment was performed to remove methylcyclohexane, followed by cooling to room temperature while stirring to obtain an aqueous resin composition. The solid content of the aqueous resin composition was 30% by weight, pH = 7.9, the viscosity was 70 mPa · s / 25 ° C., and the average particle size was 110 nm.

[Example 15]
100 parts by weight of the modified polyolefin resin obtained in Example 10 (Prototype Example 10) was used, and the surfactant was changed to 10 parts by weight of polyoxyethylene alkylamine. A composition was obtained. The solid content of the aqueous resin composition was 30% by weight, pH = 7.9, the viscosity was 68 mPa · s / 25 ° C., and the average particle size was 76 nm.

[Comparative Example 10]
An aqueous resin composition was obtained in the same manner as in Example 11 using 100 parts by weight of the modified polyolefin resin obtained in Comparative Example 5 (Prototype Example 5). The solid content of the aqueous resin composition was 30% by weight, pH = 7.3, the viscosity was 75 mPa · s / 25 ° C., and the average particle size was 108 nm.

[Comparative Example 11]
An aqueous resin composition was obtained by the same operation as in Example 12 using 100 parts by weight of the modified polyolefin resin obtained in Comparative Example 6 (Prototype Example 6). The solid content of the aqueous resin composition was 30% by weight, pH = 7.9, the viscosity was 108 mPa · s / 25 ° C., and the average particle size was 92 nm.

[Comparative Example 12]
Using 300 parts by weight of the modified polyolefin resin obtained in Comparative Example 7 (Prototype Example 7), the surfactant was changed to 10 parts by weight of polyoxyethylene alkyl ether sulfate, and the other operations were the same as in Example 12. An aqueous resin composition was obtained. The solid content of the aqueous resin composition was 50% by weight, pH = 6.8, the viscosity was 279 mPa · s / 25 ° C., and the average particle size was 86 nm.

[Comparative Example 13]
An aqueous resin composition was obtained in the same manner as in Example 14 using 100 parts by weight of the modified polyolefin resin obtained in Comparative Example 8 (Prototype Example 8). The solid content of the aqueous resin composition was 30% by weight, pH = 7.9, the viscosity was 132 mPa · s / 25 ° C., and the average particle size was 191 nm.

[Comparative Example 14]
In a four-necked flask equipped with a stirrer, a condenser, a thermometer and a dropping funnel, 100 parts by weight of the modified polyolefin resin obtained in Comparative Example 8 (Prototype Example 9), polyoxyethylene alkyl ether sulfate as a surfactant 10 parts by weight and 25 parts by weight of toluene were added and kneaded at 155 ° C. for 30 minutes. Next, 10 parts by weight of morpholine was added over 5 minutes, held for 5 minutes, and then 300 parts by weight of 90 ° C. ion-exchanged water was added over 40 minutes. An aqueous resin composition was not obtained.

[Comparative Example 15]
Using 100 parts by weight of the modified polyolefin resin obtained in Example 8 (Prototype Example 3), the addition amount of the surfactant was changed to 2 parts by weight, and the other operations were performed in the same manner as in Example 13 to obtain the aqueous resin composition. Obtained. The solid content of the aqueous resin composition was 30% by weight, pH = 6.7, the viscosity was 237 mPa · s / 25 ° C., and the average particle size was 342 nm. The physical properties of Examples 11 to 15 and Comparative Examples 10 to 15 are summarized in Table 3.

  The following tests were conducted on the aqueous resin compositions obtained in Examples 11 to 15 and Comparative Examples 10 to 15. The results are shown in Table 4.

[Blocking resistance test]
The aqueous resin composition was applied to a polypropylene film that had not been surface-treated using a # 7 Meyer bar and dried at room temperature for 15 hours. The test piece was bent so that the coating surfaces overlap each other, lightly pressed with a finger, and then peeled off. The blocking resistance was evaluated from the ease of peeling.

[Adhesion test]
The aqueous resin composition was spray-coated on an ultra-high rigidity polypropylene plate so as to have a dry film thickness of 10 μm or more and 15 μm or less, and dried at 70 ° C. for 30 minutes. After leaving the test piece at room temperature for 3 days, make a cut on the surface of the coating film with a cutter to make 100 grids at 1mm intervals, and adhere cellophane adhesive tape on it in the direction of 180 degrees After peeling off 5 times, the number of remaining grids was counted.

[Heat seal strength test]
The aqueous resin composition was applied to a polypropylene film or PET film that had not been surface-treated using a # 7 Meyer bar and dried at room temperature for 15 hours. The coating surfaces are overlapped, and no. Heat sealing was performed using a 296 heat seal tester (Yasuda Seiki Seisakusho) under the conditions of 1.5 kg / cm ² , 90 ° C., and 10 seconds. Each test piece was cut to a width of 1.5 cm, peeled off using a tensile tester under conditions of 5 kg weight and 100 mm / min, and the peel strength was measured. The test was performed three times, and the average value was taken as the result.

[Storage stability test]
The aqueous resin composition was stored at room temperature, and the appearance after 3 months was observed.

[Compatibility test]
Aqueous polyurethane was blended at a solid content ratio of 1: 1 and sufficiently stirred, and stored at room temperature for 30 days to confirm the solution properties.

  As shown in Table 4, among the copolymers produced using the metallocene catalyst, those obtained by adding acrylic acid at the time of graft modification gave good results in all evaluation items. Good results were also obtained with the addition of acrylic acid except for compatibility. When a Ziegler-Natta catalyst was used instead of the metallocene catalyst, the blocking resistance, adhesion and heat seal strength were significantly reduced. Further, even when a metallocene catalyst was used, when the weight average molecular weight of the copolymer was 200,000 or more and the melting point was 135 ° C. or more, the melt viscosity was high even when an aqueous solution was attempted, and an aqueous resin composition could not be obtained. . As shown in Example 13, the physical property value is good even when the solid content concentration of the aqueous resin composition is increased, and it is suitable for high solidification.

  As shown in Comparative Example 15, when the average particle diameter exceeds 300 nm, the results of blocking resistance, adhesion, and heat seal strength are good, but the storage stability and compatibility are poor.

Test 6: Primer test Each of the aqueous resin compositions obtained in Examples 11 to 15 and Comparative Examples 10 to 15 was adjusted so that the solid content was 10% by weight. Spray coating was performed so that the thickness was 15 μm or less, and drying was performed at 60 ° C. for 30 minutes. Next, the two-component top coat white paint was spray-coated so that the dry film thickness was 45 or more and 50 μm or less, allowed to stand at room temperature for 15 minutes, and then forcedly dried at 70 ° C. for 30 minutes. The test piece was allowed to stand for 3 days, and then the following test was performed. The results are shown in Table 5.

[Adhesion test]
A cross cut test similar to the above was performed.
"Water resistance test"

  The test piece was immersed in warm water of 40 ° C. for 240 hours, the state of the coating film was visually observed, and an adhesion test by a cross-cut test was performed.

[Peel strength]
An exposed cloth is attached to the surface of each coating film using a water-based adhesive, and the backing is lined. A 1 mm wide cut is made with a cutter knife from above the cloth, and carefully peeled off from the edge to the middle so as to be peeled off between the substrate and the coating film of the present invention. The specimen prepared in this manner was peeled off at 100 mm / min using a tensile tester, and the peel strength was measured.

(Iv) Gasoline resistance test A scratch (x mark) reaching the substrate was put on the surface of each coating film with a cutter knife, immersed in gasoline, and the state of the coating film was visually observed.
Evaluation criteria:
◎: No change after 12 hours ○: Film peeling occurred after 2-12 hours Δ: Film peeling occurred after 30 minutes to 2 hours x: Paint peeling occurred within 30 minutes

[Gasohol resistance test]
Scratches (x marks) reaching the substrate were put on the surface of each coating film with a cutter knife, immersed in a solution in which gasoline and ethanol were mixed in 9/1 (vol / vol), and the state of the coating film was visually observed.

Evaluation criteria:
◎: No change after 12 hours ○: Film peeling occurred after 2-12 hours Δ: Film peeling occurred after 30 minutes to 2 hours x: Paint peeling occurred within 30 minutes

  As shown in Table 5, good results were obtained for all evaluation items for the copolymer produced using the metallocene catalyst. When a Ziegler-Natta catalyst was used instead of the metallocene catalyst, the results of all the evaluation items were bad.

Claims (9)

It is obtained by graft-modifying a propylene-based random copolymer having a melting point of 50 to 130 ° C. obtained by polymerization in the presence of a metallocene catalyst with an unsaturated carboxylic acid and / or a derivative thereof,
A weight average molecular weight of 15,000 to 200,000, and
The graft weight of the unsaturated carboxylic acid and / or derivative thereof is 0.2 to 50% by weight,
Modified polyolefin resin. It is obtained by graft-modifying a propylene-based random copolymer having a melting point of 50 to 130 ° C. obtained by polymerization in the presence of a metallocene catalyst with an unsaturated carboxylic acid and / or a derivative thereof and (meth) acrylic acid ester. ,
A weight average molecular weight of 15,000 to 200,000, and
The graft weight of the unsaturated carboxylic acid and / or derivative thereof is 0.1 to 20% by weight, and the graft weight of the (meth) acrylic acid ester is 0.1 to 30% by weight.
Modified polyolefin resin.   An adhesive comprising the modified polyolefin resin according to claim 1.   A primer comprising the modified polyolefin resin according to claim 1.   The binder for coating materials containing the modified polyolefin resin of Claim 1 or 2.   An ink binder comprising the modified polyolefin resin according to claim 1.   A polyolefin base material, an undercoat layer formed of the modified polyolefin resin according to claim 1, and a paint layer, wherein the undercoat layer is laminated on the polyolefin base material, and the paint layer is formed on the undercoat layer. Polyolefin molded body that is laminated.   A modified polyolefin resin composition comprising the modified polyolefin resin according to claim 1 or 2 and an organic solvent.   A modified polyolefin resin composition comprising the modified polyolefin resin according to claim 1, water, and a surfactant, wherein the modified polyolefin resin dispersed in water has an average particle size of 300 nm or less.